Carburator Adjustment Help - The 1947 - Present Chevrolet & GMC Truck Message Board Network

dave3156 · 02-24-2005, 05:56 PM

About two weeks ago I bought a new Edelbrock #1406 carb. with automatic choke. I put it on and installed a new fuel line and new inline fuel filter. The carb that it replaced was also a #1406. It ran fine with the old carb, but could not get past Federal exhaust emissions testing. With the new carb it easily passed the test. I am disappointed with how the engine (350, mild cam, headers, performer RPM intake) runs with the new carb. I have read on other posts that it probably needs adjusted. The idle is too high and at speeds over 80 mph the engine bogs down and will not accelerate, in fact when you hit the gas pedal nothing happens over 80 mph, it continues to go at the same speed. It acts like it is fuel starved. Also low speed WOT performance is about the same as with the old carburator. I had hoped it would be better or I would at least notice a difference. I can hear more sound when the secondaries open but performance does not seem much better. I'm guessing it needs adjusted. I went to the Edelbrock website and alot of ajustment kits and parts are available? How do I know which kit I need? I am going to have a mechanic adjust the carburator, but want to get some opinions about what I need so I can have the parts he might need when I take it in. Can anybody help?

67chevemall · 02-24-2005, 06:01 PM

Timing issue? I know retarding the distrubuter just right will pass the etest
here in Canada. Put the old carb back on and save that one for etests
Unless that was your last test.
Maybe fuel pressure. Is the new carb set up yet?mix and idle?

Bill72BB · 02-24-2005, 06:56 PM

If the timing and Fuel filters are Ok , and you want to calibrate the carb , Kit # 1487 is for the 1406.
If you still have your old 1406 you might want to see if the Jet's or rods were changed in it ,and just swap them .
I've had several of these carbs and the are real easy to get running right had the 1406 on BB for a couple of years B4 the 1411 .

dave3156 · 02-24-2005, 08:29 PM

Yeah, timing could be part of it. I didn't adjust anything on the carb yet. Just bolted it on and went. I'll check the old carb and look at the rods. I'm not sure I can tell the difference or know what to look at though.

Bill72BB · 02-24-2005, 09:59 PM

Quote:

Originally Posted by dave3156

Yeah, timing could be part of it. I didn't adjust anything on the carb yet. Just bolted it on and went. I'll check the old carb and look at the rods. I'm not sure I can tell the difference or know what to look at though.

Dave , if you have young eye's the # are stamped on the Rods and Jets , my old eyes sometimes I have to use a magnifying glass.
Stock jets are .098 primary, Secondary's are .095
Rods are .075x.047 and the springs should be yellow.

pritch · 02-25-2005, 12:39 AM

I have that same carb on my boat ( ya-I know it's not a legal boat carb) and it has always ran too rich. I usually only take it out a couple times a year so it don't really bother me much, 'cause it still goes faster than I can ski, but what jets would it take to lean it out for 5000' of altitude?

ezernut9mm · 02-24-2005, 09:31 PM

st. louis has emissions testing???? i hope this doesn't spread across the state to us.

02-24-2005, 06:01 PM	#2
67chevemall Registered User Join Date: Apr 2003 Location: NB Posts: 3,367	Timing issue? I know retarding the distrubuter just right will pass the etest here in Canada. Put the old carb back on and save that one for etests Unless that was your last test. Maybe fuel pressure. Is the new carb set up yet?mix and idle? __________________ 1968 Chevy C10 307 3ott fleetside 1967 Chevy C/10 V8, 3spd, fleetside lwb.Sold 1967 Chev C/10 step, 383, M21. SOLD

02-24-2005, 06:56 PM	#3
Bill72BB Thats the Hillbilly way Join Date: Jul 2001 Location: Torrance,Ca Posts: 5,980	If the timing and Fuel filters are Ok , and you want to calibrate the carb , Kit # 1487 is for the 1406. If you still have your old 1406 you might want to see if the Jet's or rods were changed in it ,and just swap them . I've had several of these carbs and the are real easy to get running right had the 1406 on BB for a couple of years B4 the 1411 . __________________ BILL Torrance Calif 90504 Member DUF Club Member Old Farts Club 72 3/4ton Custom Camper BB402/400 trans Dynomax Cerama-coat headers , Hei distributor ,Edelbrock 1411 air,ps,pb,leafsprings ,98 chevy 60/40 seat,S10 shoulder belts tilt,3.54 Dana 60 rear. 16" Eagle wheels with LT265/75 16 tires,Gaylord Lid,H4 headlights with 100W relay conversion. " If I knew I was going to live this long I would have taken better care of myself " Marriage changes passion...suddenly you're in bed with a relative. A GUY'S PRAYER.... Lord, I pray for a nympho with huge boobs who owns a liquor store and likes to fish and hunt and has a Harley .Amen ,

02-25-2005, 12:39 AM	#6
pritch Registered User Join Date: Mar 2004 Location: Hoytsville, Utah Posts: 3,365	I have that same carb on my boat ( ya-I know it's not a legal boat carb) and it has always ran too rich. I usually only take it out a couple times a year so it don't really bother me much, 'cause it still goes faster than I can ski, but what jets would it take to lean it out for 5000' of altitude? __________________ '68 Panel Project Boogie Chillin' '68 C-10 Ol' Green

02-24-2005, 09:31 PM	#7
ezernut9mm Registered User Join Date: Feb 2005 Location: kansas city, mo. Posts: 224	st. louis has emissions testing???? i hope this doesn't spread across the state to us. __________________ '06 silverado (daily driver) '02 nissan sentra (wal-mart warrior)

02-24-2005, 05:56 PM	#1
dave3156 Registered User Join Date: Mar 2004 Location: St. Louis, MO Posts: 336	Carburator Adjustment Help About two weeks ago I bought a new Edelbrock #1406 carb. with automatic choke. I put it on and installed a new fuel line and new inline fuel filter. The carb that it replaced was also a #1406. It ran fine with the old carb, but could not get past Federal exhaust emissions testing. With the new carb it easily passed the test. I am disappointed with how the engine (350, mild cam, headers, performer RPM intake) runs with the new carb. I have read on other posts that it probably needs adjusted. The idle is too high and at speeds over 80 mph the engine bogs down and will not accelerate, in fact when you hit the gas pedal nothing happens over 80 mph, it continues to go at the same speed. It acts like it is fuel starved. Also low speed WOT performance is about the same as with the old carburator. I had hoped it would be better or I would at least notice a difference. I can hear more sound when the secondaries open but performance does not seem much better. I'm guessing it needs adjusted. I went to the Edelbrock website and alot of ajustment kits and parts are available? How do I know which kit I need? I am going to have a mechanic adjust the carburator, but want to get some opinions about what I need so I can have the parts he might need when I take it in. Can anybody help?

02-24-2005, 08:29 PM	#4
dave3156 Registered User Join Date: Mar 2004 Location: St. Louis, MO Posts: 336	Yeah, timing could be part of it. I didn't adjust anything on the carb yet. Just bolted it on and went. I'll check the old carb and look at the rods. I'm not sure I can tell the difference or know what to look at though.



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